Answer:
in physics, a photon is a bundle of electromagnetic energy. It is the basic unit that makes up all light
Explanation:
Answer:
c
Explanation:
Friction is caused by how rough and object is, and how much the object weighs, as this causes it to drag more.
Some examples of when friction is helpful are: to help the movement of tires. When you walk, and also, when you erase. :)